3.3^x-2 + 5.3^x-2 -2.3³.3^x-2 =-414

(3+5-2.3³) . 3^x-2 =-414

-46. 3^x-2 = -414

3^x-2 = 9

x-2=2

x=4

Bài làm:

Ta có: \(3^x+5.3^{x+2}=414\)

\(\Leftrightarrow3^x\left(1+5.3^2\right)=414\)

\(\Leftrightarrow3^x.46=414\)

\(\Leftrightarrow3^x=9=3^2\)

\(\Rightarrow x=2\)

3^x + 5 . 3^{x + 2} = 414

<=> 3^x + 5 . 3^x . 3² = 414

<=> 3^x ( 1 + 45 ) = 414

<=> 3^x . 46 = 414

<=> 3^x = 9

<=> 3^x = 3²

<=> x = 2

3^x + 5.3^x+2 = 414

<=> 3^x.1 + 5.3^x.3² = 414

<=> 3^x( 1 + 5.3² ) = 414

<=> 3^x.46 = 414

<=> 3^x = 9

<=> 3^x = 3²

<=> x = 2

3^x+5.3^x+2

3^x + 5. 3^x + 2 = 0

3^x (1 +5) + 2 =0

3^x. 6 + 2 = 0

3^x. 6       = 0-2

3^x .6        = - 2

3^x             =  -2 : 6

3^x              =  -1/2

x thuộc tập hợp rỗng 

Vậy ...

a) x × 5 = 50 – 15

x × 5 = 35

x = 35 : 5

x = 7

b) x : 4 = 38 – 33

x : 4 = 5

x = 5 × 4

x = 20

c) x + 356 = 414 + 62

x + 356 = 476

x = 476 – 356

x = 120

d) x : 4 = 2 × 3

x : 4 = 6

x = 6 × 4

x = 24

2x+ 3= x+ 2
2x- x= 2- 3
x= -1
vậy x=-1
b) \(3^{x-1}+5.3^{x-1}=162 \) 

\(3^{x-1}.\left(1+5\right)=162\)

\(3^{x-1}.6=162\)

\(3^{x-1}=162:6\)\(\Rightarrow3^{x-1}=27\)

\(3^{x-1}=3^3\)

\(\Rightarrow x-1=3\)

\(\Rightarrow x=4\)

a) x² - 4x = 0

<=> x(x - 4) = 0

<=> x = 0 hoặc x - 4 = 0

<=> x = 0 hoặc x = 4

b) 4x - (3 + 5x) = 14

<=> 4x - 3 - 5x = 14

<=> - x = 14 +3

<=> - x = 17

=> x = - 17

c)\(\frac{-7^5.3^3}{7^2.\left(-3\right)^3}=\frac{-7^5.3^3}{-7^2.3^3}=\frac{7^5}{7^2}=7^3=343\)

Bài 1:

a: Ta có: \(48751-\left(10425+y\right)=3828:12\)

\(\Leftrightarrow y+10425=48751-319=48432\)

hay y=38007

b: Ta có: \(\left(2367-y\right)-\left(2^{10}-7\right)=15^2-20\)

\(\Leftrightarrow2367-y=1222\)

hay y=1145

Bài 2: 

Ta có: \(8\cdot6+288:\left(x-3\right)^2=50\)

\(\Leftrightarrow288:\left(x-3\right)^2=2\)

\(\Leftrightarrow\left(x-3\right)^2=144\)

\(\Leftrightarrow\left[{}\begin{matrix}x-3=12\\x-3=-12\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=15\\x=-9\end{matrix}\right.\)